Other mistake: For secret agents, Sydney and Dixon are not very dedicated to secret identities. At several points they refer to each other by their real names in front of other people while they are under aliases. Examples include The Confession party and The Coup Las Vegas scenes.
Color-Blind - S1-E7
Continuity mistake: When Jack meets Vaughn in the restaurant he pours some liquid into his cup. On the front shot he picks the cup up before he pours, we then cut to a reverse angle and the cup is on the table.
Factual error: At the start, just after Sydney has the phone call regarding Will, she goes to meet her dad and says that they can save Will, if they get the Rambaldi document from the CIA and the ampule from SD6. In fact, it is the other way round; the CIA have the ampule, and SD6 have the page.
Suggested correction: SD6 got the ampule off Sark after catching him when Vaughn left him to help Sydny.
I am afraid not, Vaughan recovers the ampule before leaving to save Sydney. Thus CIA still has the ampule.
Continuity mistake: After Sydney learns that SD-6 is not part of the CIA, she goes to Taipei. Just after she arrives, she takes a man's car. At this point the number plate reads DH 5578, but, in the next shot, as she is driving away, it is JU 1587. (00:51:15)
Continuity mistake: When Sydney is tortured, she loses some teeth and a stream of blood flows out the right side of her mouth. When she returns to SD-6 and speaks with the director, the blood is gone (fair enough). Outside on the street in the following shot, the blood has returned, but there's no reason to believe that she is still bleeding. (00:58:40)
Color-Blind - S1-E7
Continuity mistake: When Sloane is talking to Sydney towards the end, he slides some documents towards her. After that shot, when the shot's of Syd we can see that Sloane's holding his hands near his face, but in front shots of Sloane they're down by the desk. (00:37:30)
Factual error: Sydney is sent to Malaga, Spain, but right after the location pops on the screen it fades to the city hall in Stockholm, Sweden.
Revealing mistake: When Syd's Dad rescues her in the car park, he starts shooting at the other car. After firing one shot the slide of his gun locks back (indicating it's out of bullets), but when the angle changes he carries on firing with no problems. (00:43:20)
Revealing mistake: When Sydney and her father go into the office to talk, the office doors begin to close before Sydney uses the remote to close them. (00:13:00)
Continuity mistake: When Roger Moore is showing Sloane the bank accounts, he says "5 deposits in excess of $45 million...", but the shot just before that shows deposits of (in thousands), $9,362, $7,215, $9,010, $8,300, and $9,250. That makes $43,137,000, which isn't in excess of $45 million. (00:20:10)
Continuity mistake: When Syd is talking to her moronic handler at the magazine stand, when he says "who do you think you're talking to?", shots of him show Syd facing straight ahead, but shots of her show that she's turned towards him.
Continuity mistake: As Anna approaches Syd in the middle of the field, she reaches her hands up to her belt. In the very next shot from behind her, her arms are by her sides. (00:38:10)
Continuity mistake: In the parking garage, after Sydney knocks the machine pistol out of the hit man's hands, it lands with the barrel pointing away from The Two of them and remains in that position during their entire fight. When Sydney grabs it off the ground, the barrel is pointing toward them. (00:43:30 - 00:44:10)
Continuity mistake: When Sydney and Danny are at the pumps outside the city talking about her job, between front and back shots the hair at Sydney's left ear changes position from stray strands blowing in the wind to neatly tied back - no stray strands. (00:18:50)
Visible crew/equipment: In the first run through of Sydney driving into the dock in the car, the cable being used to pull the car is visible if you look closely in the long shot (00:01:50)
Rendezvous - S1-E21
Factual error: When Sloane is talking to Emily on the telephone, Sloane's phone emits a call waiting beep and the camera focuses on the phone's screen. There are two factual errors here: 1) The phone icon for "Line 1" near the top right hand corner of the phone display is in the "on-hook" position indicating that there is no call in place. 2) The call information is displayed incorrectly. It is obvious that this is a Cisco XML card with the text entered. (00:32:10)
Continuity mistake: In the fight scene between Sydney and Anna, Anna comes running in with her hair tied back. Her hair changes several times between being up in a ponytail and being down. (00:23:00)
Continuity mistake: When Sydney takes Danny upstairs, her hair is tucked behind her ear. When she turns to face him, her hair is no longer tucked behind her ear.
Continuity mistake: Between the pilot episode and the second episode of Season 1, the swing of the blast door on the secret base reverses. In the pilot, the hinge is on the right and it opens from the left. In episode two, the door opens from the right with the hinge on the left. (00:12:05)